1. Field of the Invention
The present invention relates generally to an image display apparatus and image display method for changing a tone of an image, and a program storage medium.
2. Description of the Related Art
In recent years, digital cameras are widely available, and digital photographs are usually saved as digital image data. When a conventional film camera is used to take a photograph, the photograph is often printed. In a case of digital image, however, a user can use a digital camera to take a digital photograph. The images can be viewed on a digital camera or image data can be loaded to a personal computer and images can be viewed on the personal computer. Therefore, this offers the user variety of ways to enjoy the photographs.
In the above circumstances, in order to allow users to enjoy image data in the same manner as they enjoy conventional print, so-called digital photo frames are realized and widely available (for example, Jpn. Pat. Appln. KOKAI Publication No, 2009-141678).
The digital photo frame makes use of features of digital method to achieve various kinds of display modes, e.g., displaying a plurality of photographs as a slide show, which cannot be achieved by a conventional photo frame for displaying a print, and further, for example, Jpn. Pat. Appln. KOKAI Publication No. 8-44867 suggests a video correction apparatus capable of applying image processing so as to generate and display, for example, an image having a different tone but still based on an original photograph (for example, a final video which appears similar to an artwork).
This allows a user to enjoy digital images as if they are not simply photographs but are paintings. However, in the technique described in Jpn. Pat. Appln. KOKAI Publication No. 8-44867, simulation is performed in units of pixels, which is insufficient in enhancing artistic quality in view of the entire image.
For this reason, Jpn. Pat. Appln. KOKAI Publication No. 2004-213598 suggests a technique for extracting features such as color information and brush touch information from an image of a painting that is actually painted by an artist and converting a taken image into a highly artistic painting-like image in view of the entire original image by applying the extracted features to the image.
Therefore, as image processing for obtaining a highly-artistic image from an original image, an image processing for generating image data so as to further enhance the artistic presentation effect in view of the entire original image can be achieved.
However, although a conventional image processing technique includes changing a tone of an image to many tones such as an oil painting, a water color painting, a pastel painting, and the like, a CPU is required to perform a large amount of arithmetic operations so as to apply the above processing, and it takes a long time to change a tone of an image.
When it takes a long time to perform conversion processing, it is difficult to try various kinds of conversion processing and select a most suitable painting tone image.